1. Field of the Invention
This invention relates to devices which resize and re-dimension spent cartridge cases, including deburring and reaming and cleaning of the cartridge case. Specifically, this invention pertains to cartridge case trimmers that trim the neck of cartridge cases by indexing on the shoulder of the case as established by the resizing die.
2. Description of Prior Art
There are numerous machines which recycle spent cartridge cases and permit them to be reused. When a cartridge is fired, the case expands, the diameter of the case is increased, because of the internal pressure. To reuse, it is common to run the cartridge case through a die to do a full body resize. When the body of the cartridge case is returned to its original size, the added size from the stretched metal is converted into extra length of the cartridge caseneck. In particular, the distance between the shoulder and mouth lengthens. It is common for 0.006 inches to 0.015 inches in length to be added. The excess length is removed based on the overall length of the cartridge measured from the cartridge head.
Current devices, such as rotating cutters, are brought to a fixed case. This usually leaves burrs on the inner and outer edges which are removed with a deburring tool. This in turn leaves a chamfer on the outer edge which may be a safety hazard. A case which has been trimmed too long and chamfered may be forced into the barrel of the weapon. When this is done, the chamfer acts as a forcing cone or collet and excess pressure will occur.
There are no known devices which index on the shoulder of the case as established by the resizing die. All known devices index on the head of the cartridge.
Accordingly, it is a object of the present invention to resize the length of the neck and trim the mouth of cartridge cases by indexing on the shoulder of the case as established by the resizing die. Cutting stops automatically when the shoulder reaches a preset location.